About

Dr. Tina Dura is an Assistant Professor of Natural Hazards at Virginia Tech, specializing in subduction zone paleogeodesy. Her research combines methods such as coastal stratigraphy, sedimentology, micropaleontology, paleoseismology, geophysical and sediment transport modeling, and sea-level research to reconstruct long-term histories of coseismic vertical deformation and tsunami inundation along subduction zone coastlines. She employs both field-based methods, including stratigraphic mapping and sediment descriptions, and laboratory-based techniques like particle size analysis, geochemical, and diatom analyses to characterize coastal sedimentary sequences and identify evidence of sudden coseismic subsidence or uplift, as well as anomalous sand beds indicative of past tsunamis. Her work involves developing earthquake and tsunami chronologies through radiocarbon, 137Cs, and OSL dating. Dr. Dura and her research group are notable for their specialization in diatom-based subduction zone paleogeodesy, a method valuable for quantifying coseismic land-level change across sharp stratigraphic contacts and identifying tsunami deposits over centennial and millennial timescales. She holds a PhD in Earth Science from the University of Pennsylvania, an MA in Geology from Central Washington University, and a BA Honors in Geology from Occidental College. Her research contributes significantly to understanding the long-term behavior of subduction zones and the geological evidence of seismic and tsunami events.

Research topics

• Oceanography
• Seismology
• Geology
• Geography
• Geomorphology
• Archaeology
• Paleontology
• Earth science
• Physical geography

Selected publications

• Paleoseismic evidence for the 1730 Mw ≥9 Chile earthquake in a former coastal lagoon: an infrequent, shallow, tsunamigenic rupture with plausible near-term recurrence

  Quaternary Science Reviews · 2026-01-08

  articleOpen access

  We report the first paleoseismic evidence jointly documenting coseismic subsidence and tsunami inundation from the 1730 Chile earthquake (Mw ≥ 9) and its trans-Pacific tsunami. At Campiche, a former coastal lagoon in Chile's Metropolitan Region, multiproxy stratigraphic, sedimentological, and microfossil data reveal a laterally continuous tsunami sand sheet that extends ∼2 km inland, sharply disrupts lagoonal mud, and shows an erosional lower contact, rip-up clasts, and mud drapes from waning flow. Accompanying shifts from freshwater to brackish–marine diatom assemblages and the sudden appearance of salt-tolerant plant remains record a persistent increase in tidal influence, indicating coseismic subsidence. Radiocarbon and luminescence ages constrain its deposition to 1698–1782 CE, consistent with historical accounts of the 1730 tsunami and the absence of any other comparable event in the written record. Campiche thus complements previously reported uplift-dominated mid-Holocene records by showing that infrequent, subsidence-generating shallow ruptures—not just deeper, uplift-producing earthquakes—are an integral component of central Chile's megathrust behavior. Remarkably, this paleoseismic archive, formed during a brief window within a ∼4000-year marine-to-terrestrial transition and preserved in an emergent, semiarid, preservation-limited margin, suggests that similar evidence may exist in other unfavorable settings. Integration of the Campiche record with historical, geophysical, and geodetic data indicates that a shallow slip deficit of ∼20 m may have accumulated since 1730, consistent with highly coupled shallow asperities, the recent shift from coastal stability to gradual subsidence, and proposed 200–650 yr recurrence intervals for large tsunamis. Taken together, these lines of evidence suggest that Chile's Metropolitan Region now lies within a plausible near-term window for another large tsunamigenic rupture. These findings underscore the need to integrate paleoseismic records and deep–shallow rupture interplay—including infrequent shallow Mw ≥ 9 events superimposed on more frequent Mw ∼8 deeper earthquakes—into tsunami-hazard models for Chile and the wider Pacific. • First paleoseismic evidence that the 1730 Chile quake was a shallow, tsunamigenic rupture. • Small emergent semiarid coastal lagoons can preserve tsunami and land-level signals. • Interplay of frequent deep and rare shallow ruptures promotes a large shallow slip deficit. • Campiche evidence places Chile's Metropolitan Region within a near-term window for a large tsunamigenic event.

  PublisherDOI

• Insights into the in-situ degradation and fragmentation of macroplastics in a low-order riverine system

  Environmental Toxicology and Chemistry · 2025-05-02 · 7 citations

  articleOpen access

  Inland riverine systems are major conduits of microplastics (MPs) to coastal environments. Plastic materials that pass through riverine systems are subjected to various degradation processes that facilitate their fragmentation into MPs. Low-order streams, a critical yet understudied part of river networks, significantly influence the fate and transport of MPs. Here, we investigate the in situ degradation of common macroplastic polymers (e.g., low-density polyethylene, polyethylene terephthalate, and polystyrene) and their fragmentation into MPs in urban and forested streams. We deployed macroplastic items and a natural biodegradable polymer (cellulose) into a stream habitat for 52 weeks. We found that regardless of stream type (forested or urban), macroplastic polymers produced MPs in 2 weeks, with polystyrene having the highest fragmentation rate (8 particles/week). We explored several degradation indices (carboxyl index, hydroxyl index, and vinyl index), which revealed that photooxidation played a role in macroplastic degradation over time. Another driver of degradation was biofilm formation observed on the surface of all items, mainly composed of diatoms. Finally, we found that field-aged macroplastics can leach plastic-derived dissolved organic. Our study narrows the knowledge gap regarding MP degradation and fragmentation in freshwater by providing real-time in situ data on the rate of polymer fragmentation in a low-order riverine system.

  PublisherOA PDFDOI

• Improving Paleotsunami Recurrence and Inundation Estimates at the Southern End of the Cascadia Subduction Zone

  Abstracts with programs - Geological Society of America · 2025-01-01

  article
  PublisherDOI

• Where have all the hazards gone? Studying complexity, uncertainty, and nonlinearity in coastal stratigraphy through Monte-Carlo simulations

  2025-03-14

  preprintOpen accessSenior author

  Coastal areas represent complex, nonlinear depositional systems that form important stratigraphic records. These records are frequently used to reconstruct past natural hazards, including earthquakes, tsunamis, and storms, as well as to investigate processes associated with sea-level changes and the impacts of climate change. Of course, the underlying assumption is that understanding past events and processes can improve our ability to anticipate future environmental changes, hazards, and their consequences. While the geologic record provides tangible evidence of past phenomena, the inherent complexity and nonlinearity of coastal systems introduce significant uncertainties. These uncertainties affect what is preserved, how it is recorded, and ultimately how the record is interpreted. Often, we address these challenges through qualitative assumptions, which may inadvertently introduce biases into our interpretations.In this study, we develop and apply a Monte Carlo-based stratigraphy generation model to explore and quantify uncertainties associated with coastal depositional environments and their responses to natural hazards. This approach provides a systematic framework to better understand how a stratigraphic record is formed due to changing environments, and how earthquakes, tsunamis, and storms influence the stratigraphic record. To analyze the impacts of these uncertainties, we employ Shannon’s entropy as our main quantitative tool. Our findings shed light on the environmental conditions under which key events are most likely to be missed or misinterpreted within the geologic record. Additionally, we demonstrate how identical hazard sequences can produce differing stratigraphic signatures depending on varying and dynamic environmental contexts. These results underscore the remarkable complexity of the stratigraphic record and its susceptibility to potential  interpretation biases. By quantifying uncertainty and variability, our work offers critical insights into the processes governing the preservation and interpretation of coastal stratigraphy, with implications for advancing hazard assessment and stratigraphic analysis.

  PublisherDOI

• Characterizing the temporal trends in the concentration and composition of microplastics over the 20th century to present in the Chesapeake Bay region

  2025-03-14

  preprintOpen access

  Plastic production first began in the early 20th century, with production rapidly growing from the mid-20 century to present day. Intertidal ecosystems, such as wetlands and estuaries, serve as significant sinks for microplastics (particles < 5 mm) due to daily tidal inundation, natural sediment accumulation processes, and inputs from atmospheric, marine and freshwater sources. Despite documented microplastics in coastal waters and sediments, quantitative studies on how their concentration and composition has changed over time are scarce. Here, we analyzed sediment cores from intertidal wetlands on both the bayside and seaside of the Chesapeake Bay to quantify microplastic concentrations and characterize polymers. We collected two 50-cm sediment cores from a bayside wetland in the Saxis Wildlife Management Area and a seaside wetland on Wallops Island National Wildlife Refuge. Microplastics were isolated, enumerated, and characterized in 1-cm intervals. Polymer characterization was conducted using a µRaman mass spectrometer. 210Pb and 137Cs analyses provided a chronology of the sediment sequences, showing that ~40 cm core depth corresponds to 1900 and ~15 cm corresponds to 1963. Data from bayside marsh revealed an increase in microplastics concentrations from the bottom (~0.47 particles/g and 5.7 fibers/g) to the top (~2.3 particles/g and 10.8 fibers/g) of the core. Dominant polymers shifted from polystyrene and nylon at the bottom to polyethylene terephthalate at the top. At the seaside marsh, preliminary data shows an overall lower concentration of microplastics (

  PublisherDOI

• When Earth Writes Its Own Story: Unraveling the Hidden Complexity of Coastal Earthquake Records Through Monte Carlo Stratigraphy

  Abstracts with programs - Geological Society of America · 2025-01-01

  articleSenior author
  PublisherDOI

• Increased flood exposure in the Pacific Northwest following earthquake-driven subsidence and sea-level rise

  Proceedings of the National Academy of Sciences · 2025-04-28 · 6 citations

  articleOpen access1st authorCorresponding

  Climate-driven sea-level rise is increasing the frequency of coastal flooding worldwide, exacerbated locally by factors like land subsidence from groundwater and resource extraction. However, a process rarely considered in future sea-level rise scenarios is sudden (over minutes) land subsidence associated with great (>M8) earthquakes, which can exceed 1 m. Along the Washington, Oregon, and northern California coasts, the next great Cascadia subduction zone earthquake could cause up to 2 m of sudden coastal subsidence, dramatically raising sea level, expanding floodplains, and increasing the flood risk to local communities. Here, we quantify the potential expansion of the 1% floodplain (i.e., the area with an annual flood risk of 1%) under low (~0.5 m), medium (~1 m), and high (~2 m) earthquake-driven subsidence scenarios at 24 Cascadia estuaries. If a great earthquake occurred today, floodplains could expand by 90 km 2 (low), 160 km 2 (medium), or 300 km 2 (high subsidence), more than doubling the flooding exposure of residents, structures, and roads under the high subsidence scenario. By 2100, when climate-driven sea-level rise will compound the hazard, a great earthquake could expand floodplains by 170 km 2 (low), 240 km 2 (medium), or 370 km 2 (high subsidence), more than tripling the flooding exposure of residents, structures, and roads under the high subsidence scenario compared to the 2023 floodplain. Our findings can support decision-makers and coastal communities along the Cascadia subduction zone as they prepare for compound hazards from the earthquake cycle and climate-driven sea-level rise and provide critical insights for tectonically active coastlines globally.

  PublisherOA PDFDOI

• An <scp>Alaska–Aleutian</scp> Subduction Zone Interface Earthquake Recurrence Model From Geology and Geodesy

  Geophysical monograph · 2024-11-27 · 1 citations

  otherOpen access

  We present an earthquake recurrence model for the subduction interface of the Alaska–Aleutian subduction zone from geodetic and paleoseismic data. To capture variations in rupture behavior along strike, we define fault sections based on geodetic coupling, prehistoric earthquake and tsunami recurrence, historical ruptures, and geologic and geophysical structure. In the 1964 M w 9.2 rupture area, which spans four fault sections, recurrence rates for section participation in presumed great ( M w 8.5+) events vary from ∼600 years (Prince William Sound section) to ∼380 years (Kodiak section), geodetic character varies substantially along strike, and geologic evidence indicates that rupture patches vary in space and time. Westward along the Semidi section, the recurrence of large, tsunamigenic ruptures is more frequent (∼220 years) based on geologic and geodetic data than previously assumed. The seismic potential of the Shumagin section, an area of low coupling, remains enigmatic despite a large ( M w 7.8) rupture in 2020. Prehistoric tsunami data indicate that inundation recurrence in the Fox Islands is ∼210 years. Paleoseismic data are lacking west of the Fox Islands, so rupture rates along the western 1900 km of the subduction interface to Komandorski are inferred from geodetic constraints.

  PublisherOA PDFDOI

• The impact of post-depositional processes on tsunami deposits - A quantitative analysis for tsunami hazard assessments

  2024-03-09

  preprintOpen accessSenior author

  Sandy tsunami deposits are essential stratigraphic markers to document the impact of tsunamis in the geologic record. Tsunami sands are also the only record of past tsunamis that can be interrogated to retrieve quantitative information about the causative tsunami event. Inversion of flow speed and flow depth from tsunami deposits is often employed to understand a tsunami event better and evaluate the impact of different tsunami events in the same stratigraphic sequence or geographic area.&amp;#160;After deposition, like any other deposit, sandy tsunami deposits are exposed to a series of processes that alter the deposits, collectively called post-depositional processes. These post-depositional processes can change the characteristics significantly. If tsunami deposits are employed to gain quantitative insights into a past event, these post-depositional processes can potentially alter respective inversion results. The influence of post-depositional processes on the inversion of flow depths and speeds has been considered but remains understudied.To gain more insight into the influence of flow speed and flow depth inversions, we present a new model to simulate different post-depositional processes, such as erosion, bioturbation, winnowing, compaction, and dissolution of minerals. We employ stochastic processes for all these sediment alteration possibilities on a grain-size distribution level. In this context, we use a large number of reference grains for each grain-size class in a given deposit and calculate an individual grain's fate depending on the post-depositional process. This new model allows us to consider different combinations of processes to simulate different sedimentary environments and to quantify the influence of different post-depositional processes with time. We employ the established TSUFLIND model to invert flow speed and depth from the altered grain-size distribution.&amp;#160;Our results indicate how individual post-depositional processes have a more significant influence on inverted flow speeds and depths than others, but they also show how they can influence each other to have a more substantial impact on the sum than individually. Furthermore, our results shed light on potential uncertainties any inversion of the flow characteristics might have depending on the sedimentary environment in which the tsunami deposit was created. In turn, this contributes to a better understanding of uncertainties in tsunami hazard assessments that include tsunami deposits.

  PublisherDOI

• Repeated Coseismic Uplift of Coastal Lagoons Above the Patton Bay Splay Fault System, Montague Island, Alaska, USA

  Journal of Geophysical Research Solid Earth · 2024-05-01 · 9 citations

  articleOpen access

  Abstract Coseismic slip on the Patton Bay splay fault system during the 1964 M w 9.2 Great Alaska Earthquake contributed to local tsunami generation and vertically uplifted shorelines as much as 11 m on Montague Island in Prince William Sound (PWS). Sudden uplift of 3.7–4.3 m caused coastal lagoons along the island's northwestern coast to gradually drain. The resulting change in depositional environment from marine lagoon to freshwater muskeg created a sharp, laterally continuous stratigraphic contact between silt and overlying peat. Here, we characterize the geomorphology, sedimentology, and diatom ecology across the 1964 earthquake contact and three similar prehistoric contacts within the stratigraphy of the Hidden Lagoons locality. We find that the contacts signal instances of abrupt coastal uplift that, within error, overlap the timing of independently constrained megathrust earthquakes in PWS—1964 Common Era, 760–870 yr BP, 2500–2700 yr BP, and 4120–4500 yr BP. Changes in fossil diatom assemblages across the inferred prehistoric earthquake contacts reflect ecological shifts consistent with repeated draining of a lagoon system caused by &gt;3 m of coseismic uplift. Our observations provide evidence for four instances of combined megathrust‐splay fault ruptures that have occurred in the past ∼4,200 years in PWS. The possibility that 1964‐style combined megathrust‐splay fault ruptures may have repeated in the past warrants their consideration in future seismic and tsunami hazards assessments.

  PublisherOA PDFDOI

Recent grants

• RAPID: Illapel Earthquake and Tsunami - Environmental Impacts on the North Central Chile Coast

  NSF · $18k · 2015–2016

• EAR-PF: SPATIAL AND TEMPORAL VARIABILITY OF COSEISMIC SUBSIDENCE ALONG THE CASCADIA SUBDUCTION ZONE

  NSF · $174k · 2017–2021

Frequent coauthors

• Benjamin P. Horton

  Earth Observatory of Singapore

  82 shared

• Jessica E. Pilarczyk

  Simon Fraser University

  38 shared

• Alan R. Nelson

  United States Geological Survey

  38 shared

• Simon E. Engelhart

  Durham University

  35 shared

• Robert C. Witter

  33 shared

• Yuki Sawai

  Geological Survey of Japan

  30 shared

• Lisa L. Ely

  23 shared

• Andrea D. Hawkes

  University of North Carolina Wilmington

  20 shared

Labs

• Dura, Tina Research GroupPI